U.S. patent number 6,371,292 [Application Number 09/594,225] was granted by the patent office on 2002-04-16 for protective cover for stacked lumber.
This patent grant is currently assigned to Olympic General Corporation. Invention is credited to George M. Hall, David Michael McCown.
United States Patent |
6,371,292 |
McCown , et al. |
April 16, 2002 |
Protective cover for stacked lumber
Abstract
A protective covering for a lumber stack is constructed by
providing an appropriately sized sheet of heavy duty heat
shrinkable plastic material, folding the side edges of the plastic
sheeting material inwardly along spaced apart longitudinally
extending lines to form top and bottom layers and joining the ends
of the top and bottom layers to define a top layer which is
imperforate throughout its entire length and width and a bottom
layer which is imperforate throughout its entire length and width
except for a lumber stack receiving slit extending along the
longitudinal center line of the bottom wall from end to the
other.
Inventors: |
McCown; David Michael
(Arlington, TX), Hall; George M. (Colleyville, TX) |
Assignee: |
Olympic General Corporation
(Reno, NV)
|
Family
ID: |
24378048 |
Appl.
No.: |
09/594,225 |
Filed: |
June 14, 2000 |
Current U.S.
Class: |
206/321; 206/497;
383/66 |
Current CPC
Class: |
B65D
65/02 (20130101) |
Current International
Class: |
B65D
65/02 (20060101); B65D 085/46 () |
Field of
Search: |
;383/37,66,67
;206/321,497 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Fidei; David T.
Attorney, Agent or Firm: O'Neil; Michael A.
Claims
What is claimed is:
1. A lumber stack protection assembly for receiving a lumber stack
having predetermined length, width, and height dimensions
comprising a rectangular sheet of plastic material having side
edges defining the width of the sheet and end edges defining the
length of the sheet;
said sheet being folded along longitudinally extending lines each
located inwardly from an adjacent side edge approximately one
quarter of the width of the sheet to define top and bottom walls
which are joined one to another along the entire width of the end
edges, the top wall being closed across its entire length and width
and the bottom wall being closed across its entire length and width
except for a slit extending the entire length of the sheet along
the longitudinal center line of the bottom wall;
said slit being openable to receive the lumber stack
therethrough.
2. The lumber stack protection assembly according to claim 1
wherein the plastic sheeting material comprises a heavy duty heat
shrinkable plastic material.
3. The lumber stack protection assembly according to claim 1
wherein the end edges of the top and bottom walls are joined
together by heat sealing.
4. The lumber stack protection assembly according to claim 1
wherein the end edges of the top and bottom walls are joined
together by an adhesive.
5. The lumber stack protection assembly according to claim 1
wherein the plastic sheeting material comprises a heavy duty heat
shrinkable plastic material and wherein the end edges of the top
and bottom layers are joined together by heat sealing.
6. A protective covering for a lumber stack comprising:
a plastic sheeting construction comprising a rectangular sheet of
plastic material having side edges defining the width of the sheet
and end edges defining the length of the sheet and folded along
longitudinally extending lines each located inwardly from an
adjacent side edge a distance substantially equal to one quarter of
the width of the sheet to define top and bottom walls which are
joined one to another along the entirety of the end edges, the top
wall being solid across its entire length and width and the bottom
wall being solid across its entire length and width except for a
slit extending the entire length of the sheet along the
longitudinal center line of the bottom wall;
a lumber stack received within the plastic sheeting construction
through the slit in the bottom wall thereof thereby forming
initially outwardly extending triangularly shaped panels which are
folded downwardly and secured adjacent the ends of the lumber
stack.
7. The plastic sheeting construction according to claim 6 wherein
the plastic sheeting material comprises a heavy duty heat
shrinkable plastic material.
8. The plastic sheeting construction according to claim 6 wherein
the end edges of the top and bottom walls are joined together by
heat sealing.
9. The plastic sheeting construction according to claim 6 wherein
the end edges of the top and bottom walls are joined together by an
adhesive.
10. The plastic sheeting construction according to claim 6 wherein
the plastic sheeting material comprises a heavy duty heat
shrinkable plastic material and wherein the end edges of the top
and bottom layers are joined together by heat sealing.
Description
TECHNICAL FIELD
This invention relates generally to the protection of stacked
lumber from damage due to weather, etc., during shipment, and more
particularly to a method of and apparatus for protecting stacked
lumber which incorporate numerous advantages over the prior
art.
BACKGROUND AND SUMMARY OF THE INVENTION
2.times.4's, 2.times.6's, 2.times.8's, plywood, and similar lumber
products are typically arranged in stacks for shipment from the
manufacturer to lumber yards, hardware stores, contractors, etc.
Stacks of lumber are typically wrapped in plastic sheeting during
transport. The plastic wrapping protects the lumber from exposure
to the elements and also provides a convenient place to identify
the manufacturer of the lumber.
In a typical application, plastic sheeting covers all four sides
and the top, but not the bottom, of a lumber stack. Heretofore two
methods have been used to wrap lumber stacks with plastic sheeting.
One method is to wrap a lumber stack with an appropriately sized
plastic sheet in the same manner that a rectangular package is
wrapped for shipping or as a gift. Another method is to use an
envelope-like construction comprising a plastic sheet with is
folded in half longitudinally and sealed at the ends. The resulting
construction is utilized by separating the plastic layers at the
open side of the envelope, fitting the envelope over a lumber
stack, then folding the ends of the envelope downwardly.
Regardless of which of the foregoing procedures is utilized to wrap
a lumber stack in plastic sheeting, it has heretofore been the
practice to secure the plastic sheeting to the lumber stack by
stapling the plastic sheeting to the lowermost layer of lumber in
the stack at spaced apart intervals around the entire periphery of
the stack. The use of staples to secure plastic sheeting to a
lumber stack is disadvantageous for at least two reasons. First,
the staples can severely damage the lumber into which they are
inserted. Second, the stapling procedure is time consuming and
therefore expensive.
The present invention comprises a method of and apparatus for
securing protective plastic sheeting around stacked lumber which
overcomes the foregoing and other difficulties which have long
since characterized the prior art. In accordance with the broader
aspects of the invention, the plastic sheeting that is utilized in
the protection of stacked lumber comprises heavy duty shrinkwrap
plastic material. The heavy duty shrinkwrap plastic material is
positioned around a lumber stack. Thereafter, the portions of the
heavy duty shrinkwrap material which are located at the ends of the
lumber stack are heated. In this manner, the heavy duty shrinkwrap
material is drawn tightly around the lumber stack and is secured
thereto without the use of multiple staples.
In accordance with more specific aspects of the invention, a layer
of heavy duty shrinkwrap plastic material is closely fitted around
a lumber stack. The portions of the heavy duty shrink wrap plastic
material which engage the ends of the lumber stack are initially
secured in place by as few as two staples. Thereafter, the portions
of the heavy duty plastic shrinkwrap material which engage the ends
and the corners of the lumber stack are heated, thereby securing
the heavy duty plastic shrinkwrap material securely to the lumber
stack particularly at the corners. Optionally, the portion of the
heavy duty plastic shrinkwrap material which extends across the top
of the lumber stack may also be heated resulting in a smooth, upper
surface.
In accordance with another aspect of the invention, an
appropriately sized sheet of heavy duty plastic shrinkwrap material
is folded along spaced apart longitudinally extending lines and is
sealed at the ends. The resulting construction is characterized by
a solid upper layer and a lower layer having an opening extending
longitudinally along the center thereof from one end to the other.
The plastic sheeting construction of the present invention is much
easier to install around a lumber stack as compared with the
envelope of the prior art in which the opening extends along the
side edges of spaced apart plastic layers. Additionally, when the
plastic sheeting construction of the present invention is installed
around a lumber stack, the end portions thereof are formed into a
rectangular flap which is easily secured in place by two staples at
each end of the lumber stack.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the invention may be had by
reference to the following Detailed Description when taken in
conjunction with the accompanying Drawings wherein:
FIG. 1 is an illustration of a first step in a prior art method of
protecting stacked lumber;
FIG. 2 is an illustration of a subsequent step in the prior art
method of FIG. 1;
FIG. 3 is an illustration of a subsequent step in the prior art
method of FIGS. 1 and 2;
FIG. 4 is an illustration of a subsequent step in the prior art
method of FIGS. 1, 2, and 3;
FIG. 5 is an illustration of a subsequent step in the prior art
method of FIGS. 1, 2, 3, and 4;
FIG. 6 is an illustration of the final step in the prior art method
of FIGS. 1, 2, 3, 4, and 5;
FIG. 7 is an illustration of a first step in the method of
protecting stacked lumber comprised in the present invention;
FIG. 8 is an illustration of a subsequent step in the method of
FIG. 7;
FIG. 9 is an illustration of a subsequent step in the method of
FIGS. 7 and 8;
FIG. 10 is an illustration of a subsequent step in the method of
FIGS. 7, 8, and 9;
FIG. 11 is an illustration of a subsequent step in the method of
FIGS. 7, 8, 9, and 10;
FIG. 12 is an illustration of a final step in the method of FIGS.
7, 8, 9, 10, and 11; and
FIG. 13 is an illustration of the result obtained from the method
of protecting stacked lumber comprised in the invention.
DETAILED DESCRIPTION
Referring now to the Drawings, and particularly to FIGS. 1-6
thereof, there is shown a method of enclosing a lumber stack in a
layer of plastic sheeting 10 which is characteristic of the prior
art. In accordance with the method 10, an appropriately sized layer
of plastic sheeting 12 is folded along its longitudinally center
line 14 thereby defining an upper layer 16 and a lower layer 18.
The ends 20 and 22 of the layers 16 and 18 are joined, typically by
heat sealing. In this manner, there is provided an envelope
characterized by an opening 24 extending along the edges of the
layers 16 and 18 opposite the folds therebetween.
In actual practice, the envelopes of FIGS. 1-6 are manufactured
from a continuous tube of plastic material. The tube is slit along
one edge thereof. Both ends of each envelope formed from the tube
are heat sealed. The tube is also perforated at the ends of each
envelope to facilitate the separation of one envelope from the
next.
The plastic sheeting envelopes of the prior art are typically
provided in rolls 30. When an individual plastic sheeting envelope
is removed from a roll 30, it must be manipulated into a vertical
orientation to align the opening 24 thereof with a lumber stack LS.
The layers 16 and 18 are then separated and extended along the
sides of the lumber stack LS. This results in triangular shapes
projections 34 extending outwardly at the opposite ends of the
lumber stack LS. As is shown in FIGS. 5 and 6, the projections 34
are folded downwardly, after which the plastic sheeting comprising
the envelope is secured to the lumber stack LS by multiple staples
36 which are driven into the lumber stack LS at spaced apart
intervals extending around the entire periphery thereof.
The use of staples to secure protective plastic sheeting around a
lumber stack is disadvantageous for at least two reasons. First,
the installation of staples is a time consuming and therefore
expensive process. Perhaps more importantly, the outermost
components of the lower layer comprising the lumber stack can be
and often are ruined by the staples which are used to secure the
plastic sheeting into place.
Referring to FIGS. 7-13, there is shown a method of and apparatus
for protecting stacked lumber which incorporates the preferred
embodiment of the present invention. In accordance with the method
40, a suitably sized sheet of heavy duty plastic shrinkwrap
material 42 is folded along spaced apart longitudinally extending
lines 44 and 46 to form an upper layer 48 and a lower layer 50. The
opposite ends 52 and 54 of the upper and lower layers 48 and 50 are
then joined. The joining step is typically carried out by heat
sealing, however, various types and kinds of adhesives may be
utilized to join the ends of the upper and lower layers 48 and 50
depending upon the requirements of particular applications of the
invention.
In actual practice, the envelopes of FIGS. 1-6 are manufactured
from a continuous tube of plastic material. The tube is slit along
the bottom thereof. Both ends of each envelope formed from the tube
are heat sealed. The tube is also perforated at the ends of each
envelope to facilitate the separation of one envelope from the
next.
The resulting lumber stack protection assembly comprises an upper
layer 48 which is entirely solid throughout its length and width.
The lower layer is differentiated from the upper layer 48 in that
it is entirely solid throughout its length and width except for an
opening 56 which extends longitudinally along the center line of
the lower layer 50 from the end 52 to the end 54.
The foregoing steps result in a lumber stack protection assembly
comprising the present invention. The lumber stack protection
assembly may be supplied in rolls 60. When an individual lumber
stack protection assembly incorporating the invention is removed
from a roll 60, it is easily centered over a lumber stack to be
protected with the opening 56 thereof aligned with the center line
of the lumber stack LS. The difficulty which has characterized the
proper alignment of the opening extending along one side of the
envelope of the prior art with the lumber stack to be protected is
thereby eliminated.
After the lumber stack protection assembly of the present invention
is aligned with a lumber stack to be protected, the opposite sides
of the bottom wall 50 thereof are separated and extended along the
sides of the lumber stack LS. This results in rectangularly shaped
projections 62 which are folded downwardly and secured in place by
two staples 64 which are driven into the ends of the lumber
stack.
Referring particularly to FIGS. 12 and 13, the next step in the
method of the present invention comprising the application of heat
to the portions of the lumber stack protection assembly which are
located at the ends and the corners of the lumber stack. In this
manner the heavy duty plastic heat shrink material which is
utilized in the fabrication of the lumber stack protection assembly
is drawn tightly into engagement with the corners of the lumber
stack in the manner indicated at 66. In this manner the lumber
stack protection assembly is tightly secured to the lumber stack LS
without requiring the use of multiple staples driven into the
lumber stack at spaced apart intervals around the entire periphery
of the lower most layer thereof.
The method of the present invention includes the optional step of
applying heat to the portion of the lumber stack protection
assembly which extends over the top of the lumber stack. The
optional step of heating the top surface of the lumber stack
protection assembly results in a covering for the top of the lumber
stack which is entirely smooth and wrinkle free. As will be
appreciated by those skilled in the art, in many instances lumber
stacks are positioned one on top of another for transport in which
case the step of heating the portion of the plastic sheeting
construction 60 extending over the top of the lumber stack is
usually considered unnecessary.
Although preferred embodiments of the invention have been
illustrated in the accompanying Drawing and described in the
foregoing Detailed Description, it will be understood that the
invention is not limited to the embodiments disclosed but is
capable of numerous rearrangements, modifications, and
substitutions of parts and elements without departing from the
spirit of the invention.
* * * * *